Deep well Line shaft pumps for offshore application

[vjr0512]

Presently we are in detail engineering phase for the procurement of deepwell line shaft pumps (API: VS1 type, length approx 30 metres long ) for installation in the Hull Tanks of FPSO for Condensate/MEG/Oil services. In our design, the column pipes of these pumps are normally supported to the Tank walls at intermediate locations through Guide ring, Centralizer & support arrangement (no Caisson or Stilling tube).

Whether these type of pumps are supported on the tank walls only?

For my project , the tank deflections stated are upto +/- 20 mm. I would like to know that how are these pumps are designed to accommodate the Tank deflections (upto +/- 20 mm.) due to the ship motion when the the gap between the guide ring and Centralizer is ~10mm only . Also, we understand there are similar pumps whose pipe stacks are rigid connected to the tank.

Thanks to furnish the details of the normal supporting arrangements for such deep well pumps in the Hull tanks and whether the tank deflections +/- 20 mm are reasonable values?

 

[DubMac]

Not really clear on your design layout. Important to know whether your column assembly has an enclosed lineshaft or the lineshaft is product lubricated (lieshaft is open to the product flowing inside of the column).

Also what diameter is column, lineshaft? What is the lineshaft bearing spacing, what is lineshaft bearing material? Certainly your are using flanged coulumn?? Wall thickness of column?? How many supports to the tank wall and where are they located?? Inquiring minds want to know.

This could be called a "barge unloading" service. Several manufacturers have special designs for just this service. Johnston Pump used to have a very successful design that used submersible motor that essentially eliminates the lineshaft issues. They are now owned by Sulzer Pump.

 

[ApplicationENG]

DubMac may have asked a few too many questions but you get the idea. More technical details are required.

Furthermore, all the major players are well versed in these offshore applications - ITT Goulds Pumps, Flowserve, and Sulzer.